_Take of the diachylon one pound, purified mercury half a pound, triturate the mercury with a little hog’s lard or turpentine, then melt the diachylon, and incorporate the triturated mercury into it._ This is principally fit for venereal cases, for buboes, and other hard tumours; it may also be put to shankers and very bad ulcers; but it should never be used unless necessity requires it. 22. _Blistering plaister_: _Take Spanish flies eight ounces finely powdered, common drawing plaister one pound, melt the plaister and sprinkle the powdered Spanish flies till all is well incorporated, then make it into rolls according to art._ This is intended for rising blisters. In regard to the use of this, I have only to observe, that it should be made use of only, when the greatest necessity requires it; that is, in bringing on a crisis of a fever, which I shall point out in its proper place. At present I shall only speak of its application. Whatever place is intended to be blistered, either the neck, between the shoulders, or the calf of the leg, let the place first be cleaned with a little vinegar, and rubb’d till it becomes red, then let the blistering plaister, the bigness of the palm of the hand, pretty thickly spread, (best upon leather) be laid on the part, and remain there for about twelve hours, and be tied on, that it may not shift: at that time the blister will rise; let it be cut to let the water out, (but care should be taken not to pull off the skin, as is frequently practiced) dress it with _Turner’s Cerate_, spread upon a thin rag, (or what is still better, dry lint) and let that dressing be shifted once every twelve hours, till all is healed up. I shall now proceed to the inner part of the chest. A. _Spirit of wine camphorated._ _Take spirit of wine rectified one quart, camphor two ounces, mix it, and let the camphor be dissolved in it._ This is an external application, for bruises and other inflammations, where discussion, or dispersion of humours is necessary, its chief benefit is in sprains, dislocations, and fractures. I have this however to observe with the camphorated spirit, that though it is exceedingly useful in the forementioned, and in some rheumatic cases, yet it should be used with caution, and not too plentifully, as it is liable to dry up the vessels, and might incline the limb to wasting, if too freely made use of. B. _Liniment of soap._ _Take spirit of wine rectified one quart, distilled oil of rosemary one drachm, camphor one ounce, castile soap half a pound; cut the soap small, and let the whole be mixed and dissolved._ This is an excellent external medicine for sprains, rheumatism, bruises, &c. This medicine is commonly called opideldock, and in all such cases is far superior to the spirit of camphor singly; unless where the constitution is sluggish, and requires a greater stimulus; in general, however, this excellent composition will supply the place of both.[10] Footnote 10: